Pumps, ventilation and refrigeration have different operating patterns. Check backup energy, simultaneity and starting for every critical system.
Function list
Record required functions: water, ventilation and food storage. Agree acceptable interruptions and possible water storage rather than assuming every load is continuous.
Starting and power
A pump or compressor may need a brief start demand above running power. Obtain documented or measured data and check inverter and BMS capability for its duration.
Energy budget
Use a refrigerator’s daily profile under relevant conditions and pump run time and cycling. Ventilation often runs for long periods, so modest power can accumulate substantial energy use.
Control and protection
Staggered starting can reduce simultaneous peaks if equipment permits it. Define critical circuits, transfer, protection and restart behaviour in the electrical design.
Common mistakes
Do not size an inverter solely from average daily energy. Consider winter battery temperature, starting charge and sensor or control failure.
| Item | Parameter | Check / result |
|---|---|---|
| Pump | Starting and cycles | Peak check |
| Ventilation | Long operation | Energy |
| Refrigerator | Cycles and temperature | Daily profile |
What this means for your project
Prepare a measured critical-appliance list. Test simultaneous starting and the full transfer scenario before acceptance.
Sources and scope of review
Related reading
- Critical Loads: Where to Start with Backup Power
- How to Size a Home Battery
- How to Choose an Inverter for Backup Power
